Naphthenic acids, reaction products with diethylenetriamine

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on test type (migrated information)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Rationale for read-across: naphthenic acid is presumed to be the toxic metabolite of NA-DETA Rationale for assigning reliability of 2: read-across, scientifically well performed study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Naphthenic acids

EC Number:

215-662-8

EC Name:

Naphthenic acids

Cas Number:

1338-24-5

Molecular formula:

"CnH2n+zO2, where n = carbon number and z = homologous group series number: z = 0 when no ring structures are present, z = -2 when 1 ring is present, z = -4 when 2 rings are present etc Result of high resolution mass spectroscopy of 4 naphthenic acids samples from different suppliers/sources: Ring distribution of aliphatic fraction: Z = 0 15-30% Z = -2 35-50% Z = -4 10-25% Z = -6 1-7% Z = -8 0-2% Z <= -6 1-5% (unsaturated compounds) Z >= -8 0-2% (unsaturated compounds) C<= 18 8-15% (N-containing compounds) C > 18 0-2% (N-containing compounds) Unknown 0-2% Distribution of carbon number (n) of 4 naphthenic acids samples from different suppliers/sources (n):C4-C27 (main: C8-C20)

IUPAC Name:

Naphthenic acids

Test material form:

other: oily liquid

Details on test material:

Blend of naphthenic acids from three sources.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

Male dosing was for 28-29 days
Females were dosed for 39-53 days

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 100, 300, 900 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

12

Control animals:

yes, concurrent vehicle

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

unspecific toxic signs in females of 900 mg/kg bw

Body weight and weight changes:

no effects observed

Description (incidence and severity):

no statistically significant effect

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

no statistically significant effect

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

alterations found in liver, kidney, thyroid, thymus and adrenal

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

100 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects

Results: F1 generation

General toxicity (F1)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

reduced survival of pubs from birth to lactation day 4

Mortality / viability:

mortality observed, treatment-related

Description (incidence and severity):

reduced at 900 mg/kg bw

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

reduced for pubs of 900 mg/kg bw

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

100 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Number of pubs born; Percentage of pups surviving from birth to termination PND 4

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Parental toxicity data:

Table 1. Results of Assessments of hematology and clinical chemistry parameters which were statistically different from control values.^1
Parameter Measured	Corn Oil Control	100 mg/kg/day	300 mg/kg/day	900 mg/kg/day
Males, data taken at terminal sacrifice
Red Blood Cell Count (10^6/ul)^2	9.22 ± 0.54	9.28 ± 0.28	8.91 ± 0.34	8.78 ± 0.22*
Hemoglobin (g/dL)^2	15.7 ± 0.72	15.8 ± 0.48	15.2 ± 0.54	14.7 ± 0.44*
Hematocrit (%)^2	48.1 ± 2.4	48.6 ± 1.6	46.5 ± 1.5	45.0 ± 1.8**
Platelet (10^3/ul)^2	854 ± 151	885 ± 84	803 ± 144	976 ± 87**
Leukocytes, absolute (10^3/ul)^2	0.02 ± 0.02	0.03 ± 0.02	0.02 ± 0.02	0.04 ± 0.03*
RDW (%)^2	11.4 ± 0.4	11.5 ± 0.4	11.6 ± 0.4	12.5 ± 0.6**
HDW (g/dL)^2	2.58 ± 0.10	2.68 ± 0.12	2.76 ± 0.16*	2.77 ± 0.27*
Females, data taken at termination (lactation day 4)
White blood cell count^2	5.15 ± 1.30	6.89 ± 1.58	7.68 ± 2.24*	7.59 ± 1.85*
APTT (seconds)^2	16.8 ± 1.9	15.9 ± 2.3	15.8 ± 3.1	13.9 ± 1.4 *
Lymphocytes, absolute (10^3/ul),	3.32 ± 0.61	4.50 ± 1.42	5.11 ± 1.75*	4.96 ± 1.60*
Monocytes, absolute (10^3/ul)	0.11 ± 0.10	0.24 ± 0.21	0.21 ± 0.12	0.35 ± 0.23*

 

1. Parameters not affected by treatment included:

a. Males – white blood cell count, mean corpuscular volume (fL), mean corpuscular hemoglobin (pg), mean corpuscular hemoglobin content (g/dL), prothrombin time (sec), APTT (sec), reticulocytes (%), reticulocytes, absolute (10³/ul), MPV (fL), neutrophils (%), lymphocytes (%), monocytes (%), eosinophils (%), basophils (%), leucocytes(%), neutrophils, absolute (103/ul), lymphocytes, absolute (10³/ul), monocytes, absolute (10³/ul), eosinophils, absolute (10³/ul), basophils, absolute (10³/ul).

b. Females – red blood cell count (10⁶/ul), Hemoglobin content (g/dL), hematocrit (%), mean corpuscular volume (fL), mean corpuscular hemoglobin (pg), mean corpuscular hemoglobin content (g/dL), platelet count (10³/ul), prothrombin time (sec), reticulocytes (%), reticulocytes, absolute (103/ul), ), MPV (fL), neutrophils (%), lymphocytes (%), monocytes (%), eosinophils (%), basophils (%), leucocytes(%), neutrophils, absolute (10³/ul), eosinophils, absolute (10³/ul), basophils, absolute (10³/ul), Leukocytes absolute (10³/ul), RDW (%), HDW (g/dL)

 

2. Data given as mean + SD

* = p < 0.05, ** = p < 0.01

 

Table 2. Statistically significant changes in terminal body weights and organ weights.The data are given as mean + SD.
Parameter	Sham Control	Corn Oil Control	100 mg/kg/day	300 mg/kg/day	900 mg/kg/day
Males
Final Body Weight	467 ± 27	454 ± 45	448 ± 45	439 ± 34	412 ± 28
Liver	15.61 ± 1.43	13.46 ± 2.01	13.98 ± 2.04	15.69 ± 1.83*	19.94 ± 2.08**
Kidney	3.51 ± 0.25	3.21 ± 0.20*	3.38 ± 0.39	3.53 ± 0.33	3.77 ± 0.46**
Heart	1.46 ± 0.09	1.46 ± 0.21	1.41 ± 0.14	1.43 ± 0.13	1.32 ± 0.13
Thyroid/parathyroid	0.019 ± 0.002	0.019 ± 0.001	0.020 ± 0.002	0.020 ± 0.002	0.020 ± 0.002
Epididymis (LT)	0.57 ± 0.14	0.60 ± 0.05	0.60 ± 0.04	0.66 ± 0.05*	0.63 ± 0.06
Epididymis (RT)	0.62 ± 0.04	0.62 ± 0.06	0.61 ± 0.03	0.66 ± 0.04	0.65 ± 0.06
Females
Final body Weight	335 ± 25	313 ± 23	301 ± 30	294 ± 24	289 ± 24
Liver	13.6 ± 2.0	11.7 ± 1.5	12.1 ± 1.1	13.3 ± 1.5	17.9 ± 2.4**
Kidney	2.39 ± 0.17	2.07 ± 0.18*	2.11 ± 0.15	2.05 ± 0.25	2.17 ± 0.19
Heart	1.21 ± 0.23	1.10 ± 0.10	1.08 ± 0.10	1.07 ± 0.11	1.01 ± 0.13
Lungs	1.36 ± 0.13	1.40 ± 0.13	1.26 ± 0.12*	1.20 +± 0.12**	1.20 ± 0.07**
Uterus/Vagina	1.07 ± 0.19	1.00 ± 0.14	0.86 ± 0.08*	0.88 ± 0.11*	0.85 ± 0.12*

* = p < 0.05, ** = p < 0.01

 

Table 3. Summary of microscopic findings
Doses, mg/kg/day	Males				Females
	Corn Oil	100	300	900	Corn Oil	100	300	900
N	12	12	12	12	9	12	10	10
Kidney
Hyaline Droplets	0	3	10**	11**	0	0	0	0
Minimal	0	3	9**	9**	0	0	0	0
Mild	0	0	1	2
Nephropathy	0	0	2	9**	0	0	0	0
Minimal	0	0	2	5*	0	0	0	0
Mild	0	0	0	4
Liver
Hypertrophy, hepatocellular, centrilobular	0	0	0	8**	0	0	0	10**
Minimal	0	0	0	8**	0	0	0	10**
Vacuolation, hepatocellular	2	1	2	0	0	1	0	2
Minimal	1	1	2	0	0	1	0	2
Mild	1	0	0	0	0	0	0	0
Thymus
Depletion, lymphoid, cortex	0	0	0	0	0	1	0	5
Minimal	0	0	0	0	0	1	0	4
Mild	0	0	0	0	0	0	0	1
Thyroid
Hypertrophy, epithelial	0	6	9*	11**	0	3	4	8**
Minimal	0	6	9**	11**	0	3	4	6*
Mild	0	0	0	0	0	0	0	2
Vacuolation, cytoplasmic	0	6	9**	10**	0	3	4	8**
Minimal	0	6	9**	10**	0	3	4	8**
Adrenal Cortex
Vacuolation, cytoplasmic	0	2	3	2	0	0	0	2
Minimal	0	2	3	2	0	0	0	1
Mild	0	0	0	0	0	0	0	1
Heart
Cardiomyopathy
Minimal	4	7	8*	8*	3	3	2	5
Mild	2	0	0	0	0	0	0	0

* = p < 0.05, ** = p < 0.01

Data on reproduction performance and offsprings

Table 1. Summary of reproductive parameters assessed in the repeated dose/reproductive toxicity study of naphthenic acids.
Dose (mg/kg bw)	Corn Oil Control	100 mg/kg/day	300 mg/kg/day	900 mg/kg/day
Number of females paired	12	12	12	12
Number of females mated	12	12	10	11
Number of females pregnant^a	9	12	10	11
Number of females with litters	9	12	10	11
Precoital interval (days)	1.4 ± 0.7	2.3 ± 1.1	4.2 ± 3.3 *^b	3.8 ± 3.5
Gestation length (days)	21.4 ± 0.6	21.9 ± 0.3	22.0 ± 0.5	22.1 ± 0.5
Corpora lutea	15.6 ± 2.3	14.0 ± 1.4	15.1 ± 3.0	13.8 ± 2.1
Implantation sites	15.0 ± 2.4	13.6 ± 1.1	13.0 ± 1.2	12.2 ± 3.7
Number born	14.1 ± 1.9	12.9 ± 1.1	12.0 ± 1.6	10.8 ± 3.8 *
Post-implantation loss (%)	6.0	5.1	7.7	11.5

 

a. Pregnant = uterine implantation sites

b. A single female in the 300 mg/kg bw group had a pre-coital interval of 13 days

 

* = p < 0.05, ** = p < 0.01

Table 2. Survival, viability and growth of offspring
Dose (mg/kg bw)	Corn Oil Control	100 mg/kg/day	300 mg/kg/day	900 mg/kg/day
Number of viable litters	9	12	10	11
Number of pubs born alive/litter	13.9 ± 1.9	12.9 ± 1.1	10.1 ± 4.0 *	9.6 ± 4.0 **
Percentage of pubs surviving from birth to PND 4	98.1 ± 3.8	100 ± 0.0	88.0 ± 24.5	67.7 ± 40.6
Pubs (litters) found dead or euthanized in extremis	1(1)	0(0)	12(5)	38(8)
Sex ratio (% males / litter)	58.9 ± 9.6	53.9 ± 9.6	55.2 ± 19.1	58.1 ± 22.7
Pub weight PND 1 -males	7.0 ± 0.5	6.7 ± 0.6	6.7 ± 0.5	5.7 ± 0.8 *
Pub weight PND 1 -females	6.6 ± 0.6	6.5 ± 0.6	6.4 ± 0.4	5.6 ± 1.1
Pub weight PND 4 -males	9.7 ± 1.1	9.4 ± 1.2	9.4 ± 0.9	7.2 ± 1.5 **
Pub weight PND 4 -females	9.1 ± 1.0	9.0 ± 1.0	8.8 ± 0.7	7.3 ± 1.5 **

 

* = p < 0.05, ** = p < 0.01

Applicant's summary and conclusion

Conclusions:

The commercial naphthenic acid was investigated for its reproduction toxicity according to the OECD Guideliine 422. The NOAEL was 100 mg/kg bw both for parental and offsprings. The introduced study is proposed to be used to derive the reproduction toxicity of NA-DETA by read-across.

Executive summary:

The commercial naphthenic acid was investigated for its repeated dose toxicity according to the OECD Guideline 422. The applied doses were 0, 100, 300 and 900 mg/kg bw.

All animals survived to scheduled termination except two females of 900 mg/kg bw group. The terminal body weight of males and females of 900 mg/kg bw were reduced. Reduced red blood cell count for males of 900 mg/kg bw and increased white blood cell count for females of 900 and 300 mg/kg bw were observed. Liver weight was increased for animals of 900 mg/kg bw and kidney weight was increased for males only in this group. The histopathological findings comprised hepatocellular hypertrophy, hyaline-droplet nephropathy, cortial lymphoid depletion in thymus, epithelial hypertrophy and cytoplasmic vacuolation of the thyroid gland and cytoplasmic vacuolation in the adrenal cortex. The NOAEL was 100 mg/kg bw for parental animals.

With respect to the reproductive/developmental toxicity investigation, reduced live pubs at birth and reduced survival rate from birth to PND 4 was found at doses of 300 and 900 mg/kg bw and reduced pub weights at dose of 900 mg/kg bw. The NOAEL for reproductive/developmental toxicity was 100 mg/kg bw. 

The introduced study is proposed to be used to derive the reproduction toxicity of NA-DETA by read-across.